1. Field of the Invention
The present invention relates to a semiconductor device manufacturing method and a semiconductor manufacturing apparatus, and more particularly, to a semiconductor device manufacturing method including a silicon nitride film manufacturing step using a thermal CVD (Chemical Vapor Deposition) method, and to a semiconductor manufacturing apparatus preferably used for the method.
2. Description of the Related Art
Conventionally, it is common that a silicon nitride film used in a semiconductor device is formed using mixed gas of SiH2Cl2 (DCS, hereinafter) and NH3.
According to this method, however, it is necessary to form the silicon nitride film at a temperature as high as 700° C. to 800° C. and as a result, there is a problem that impurities are adversely diffused deeply into a shallow diffused layer and a semiconductor device element can not be formed small in size. Further, there is a problem that NH4Cl (ammonium chloride), which is a by-product of reaction, adheres to a discharge port, this NH4Cl generates rust on a metal surface, and metal contamination is generated on a semiconductor wafer.